MICROSCOPE IN MANUFACTURES 



Examination of the raw product under the micro- 

 scope will reveal both long and short fibres. The 

 former are the more valuable and are used in the 

 manufacture of linen, the latter are made into tow. 

 The long fibres, which are derived from the upper 

 parts of the flax plant have thickened edges and 

 a very small lumen. The short fibres, used for 

 making tow, come from the lower part of the 

 stem and the roots of the plant. Each fibre has 

 a broad lumen and is very similar to hemp fibre. 

 Examination of all these fibres, by the way, is best 

 made in water as described under cotton. 



Hemp is another bast fibre and as we have 

 remarked it resembles the short fibres of flax; 

 there is a broad lumen with an indistinct margin. 

 If we have an opportunity of comparing these fibres 

 under the microscope we shall see that many of 

 those of hemp have forked ends. This is very char- 

 acteristic of the plant and is never found in flax, 

 therefore it affords a ready means of distinguishing 

 hemp from flax. Fine linen should never contain 

 hemp, so that if our object be to test the quality 

 of a sample of linen by microscopic examination, 

 we must keep a sharp look out for the forked fibres 

 of hemp. In coarse linen these fibres occur for 

 hemp is used in its manufacture. 



Jute, another important fibre is readily distin- 

 guished under the microscope, for its margins have 

 perfectly smooth walls and its lumen is wide in 

 some places, narrow in others and interrupted 

 altogether in places. 



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